1. Field of the Disclosure
This disclosure generally relates to a human interface device and, more particularly, to a click-event detection device capable of eliminating interference from ambient light.
2. Description of the Related Art
Portable electronic devices are popular nowadays for their excellent operating convenience. Most portable electronic devices provide a display screen for a user to watch the operating states thereof and a peripheral device, e.g. an optical finger mouse, for the user to perform the cursor control or to select an application program to be executed.
Please refer to FIG. 1, it shows a schematic diagram of a conventional optical finger mouse 8 which includes a control surface 81, a light source 82, an image sensor 83 and a processing unit 84. The finger 9 of a user is operated on the control surface 81 in order to correspondingly control an electronic device 7 coupled to the optical finger mouse 8. The light source 82 is configured to provide light to the control surface 81. When the finger 9 contacts the control surface 81, it can reflect the light irradiated from the light source 82. The image sensor 83 receives reflected light from the finger 9 to accordingly output a plurality of image frames. The processing unit 84 calculates a contact status of the finger 9 according to the image frames so as to control the electronic device 7.
However, as the control surface 81 can be made of material that is transparent to the light of a predetermined spectrum, not only the light irradiated from the light source 82 but ambient light, within the predetermined spectrum, outside the optical finger mouse 8 can penetrate the control surface 81 and be detected by the image sensor 83. The image frames outputted from the image sensor 83 can be interfered to degrade the image quality thereof such that the calculation accuracy of the processing unit 84 is degraded.
Accordingly, the present disclosure provides a click-event detection device capable of eliminating interference from ambient light thereby effectively improving the identification accuracy.